The Onkyo HT-SP904 features true 5.1 surround sound with a 230-watt RMS powered subwoofer. The HT-SP904 is centred on a 1-disc DVD player with 1080p and HDMI support, as well as a built-in NTSC TV tuner and a radio tuner. The player utilizes Onkyo’s proprietary amplifier, equalizer, and gain volume circuitry and digital signal processing with an emphasis on providing the cleanest signal possible.